The function of the exhaust pipe of the car on the car body plays the role of damping and noise reduction and prolonging the life of the exhaust muffler system. The main material of the exhaust pipe is stainless steel. For a typical car, since the exhaust gas of the car leaves the engine at high pressure. The noise generated may cause madness. At this time, the main muffler is the exhaust pipe of the car, and the muffler is installed inside the car. The device greatly reduces the noise of the car. The main working principle is to divert the airflow through multiple channels. These shunts only see each other colliding with each other so that the flow velocity of the airflow is gradually reduced. This cycle is repeated, and finally, the exhaust gas is discharged through the exhaust pipe of the automobile. So that the noise is reduced! Thereby achieving the effect of daily car noise reduction.


Fault phenomenon: A Dongfeng EQ1090D car has a shooting phenomenon in the muffler during driving. During the parking check, when the ignition coil high-voltage total fire line is unplugged. It can test fire at 34mm from the cylinder block, pull the distributor to cut off the electric contact or shake. When the crankshaft was turned, the flashover was normal. But it was found that the distributor’s power-off contact had an ablation. After grinding the contacts with sandbars and adjusting the clearance to 0.35-0.45mm. The engine runs normally after starting. But when the car travels for about 40 kilometers, the muffler appears again.
Fault check and elimination: According to the above phenomenon, the reason for the muffler firing was carefully analyzed. In order to find out the faulty knot, the ignition sequence, the spring force of the distributor contact arm spring force, the ignition timing, the spark plug, etc. were not found. Continue to check the carburetor air filter and valve clearance. The engine was started again and it was working normally. But it didn’t take long for the old disease to recur.
Check the distributor part again. Through disassembly and careful inspection, it was finally found that the copper glue wire of the breaker contact arm to the low-voltage terminal broke at the corner. It leaves only a few thin copper wires connected. After the broken copper glue line is replaced, the fault phenomenon disappears.

Fault analysis: When the copper wire of the low-voltage wire of the distributor is broken. The cross-sectional area of the wire is reduced. So that the resistance of the primary circuit is increased, the current in the circuit is reduced. And the high voltage generated by the ignition coil is insufficient. When the engine temperature is low, although the starting is more difficult. The engine can run normally after starting. After the temperature of the engine rises, the temperature of the ignition coil increases and the resistance increases with the temperature rise. Therefore, the high voltage generated by the ignition coil is even more insufficient. And the high-voltage spark is weaker or even broken. Due to the occasional fire, the unburned combustible mixture in the cylinder is discharged into the muffler. When it is expanded in the muffler, the spark in the exhaust gas is detonated, which is manifested by the muffler firing.
Maintenance knowledge
The first thing to note is to prevent water from entering inside the muffler. When driving on a deep water surface or washing a car, prevent water from entering inside the muffler. If you accidentally enter the water. You should start the engine for idle heat for at least 10 minutes, try to drain the internal water. And add anti-rust oil inside the muffler, here to emphasize the specific practice of refueling:

First of all

Remove the muffler, block the drain hole at the lowest position in the middle of the muffler. Then add anti-rust oil from the muffler and engine connection, shake the muffler to let the anti-rust oil evenly enter the cylinder, then install the muffler. Because the muffler temperature gradually rises, anti-rust When the oil is heated. It will evaporate, and the muffler will emit blue smoke at the tail. But the blue smoke will disappear after about 20 kilometers. After the blue smoke disappears, remove the blockage of the drain hole. It is also recommended that the new car is refueled and maintained after the card is put on. And the refueling maintenance should be carried out once every six months.


This is the problem of discoloration of the muffler that many people are concerned about. When the car encounters a difficult start condition, first turn off the choke to start the engine, and pay attention to open the choke in time. Never drive high speed and low gear in the state of closing the choke, which will cause damage to the engine and muffler. Secondly, it is necessary not to drive the throttle at high speed for a long time. Because when the surface of the muffler is oily, after driving Will to change the color of its surface to yellow. In addition, when a large amount of dirt such as dirt is stuck on the surface of the muffler. It must be cleaned in time to avoid affecting its heat dissipation function.


Although the exhaust pipe is not a precision part inside the car and is exposed, many people think it must be a durable part. Therefore, even if it is covered with dirt, it will be considered normal. However, it is very important that the exhaust pipe can connect the foreign matter with the interior of the car. And its main function is to discharge the exhaust gas inside the car. However, if the driver is not driving properly, the substances harmful to the inside of the car will enter the vehicle through the exhaust pipe. Therefore, the maintenance of the exhaust pipe is in various senses the maintenance of the interior of the car.